This guide will show you how to turn any CircuitPython powered board with 4+ GPIO pins into an AVR progammer all on its own. No software like avrdude is needed, this software will program the chip all on its own, just drag the HEX file onto the CircuitPython disk drive.

I’m currently working on a project that requires a cheap, low-power microcontroller that’s programmable through Arduino and has a few more pins than the ATtiny85. That’s where I found the ATtiny84A. It has many of the same features as the ATtiny85, but has 12 I/O pins instead of six.